The F/A-352B Longsword was a three-seat, twin-engine, atmosphere and exoatmospheric-capable, ground and carrier-based strike starfighter, used by the United Nations Space CommandNavy during the Galactic War and Swarm War. The successor to the earlier F/A-352A Longsword, The F/A-352B was a smaller and more advanced derivative of the ubiquitous Human-Covenant War-era fighter. The Longsword could be outfitted with a range of electronic equipment, weaponry and other hardware, allowing it to fulfill a range of combat and non-combat functions. The standard configuration included two internal 50 millimetre railguns, as well as a range of air-to-air missiles and air-to-surface weapons. As the UNSC Navy's strike fighter, the Longsword's responsibilities comprised primarily performing an air-to surface attack role, while retaining the capacity to attack air targets and warships. This flexibility was crucial to the Navy, fitting its defensive and expeditionary, and atmospheric and exo-atmospheric operating environments.

Designed and initially produced by Misriah Armouries, the first Longswords to fly in 2580 were in fact F/A-352As heavily modified into prototype 352Bs. Full production began in 2587, after several years of technical troubles stalled development. Production commenced only after Misriah sold the the contract for the problematic aircraft to Chevron Aerospace, which itself exceeded the development budget in bringing the impressive but temperamental design to production. The Longsword entered service with the UNSC Navy in 2589, replacing the upgraded F/A-352A on a one-for-one basis.

Contents

History

Developmental History

Operational History

Role

As a multirole strike starfighter, the Longsword was designed from the outset with a 'dual role' function in mind; primarily operating in the air-to ground attack role, while also having sufficient dedicated fighter capabilities to attack target aircraft. In addition to this, it was capable of engaging enemy capital ships with dedicated weaponry, which was seen as a 'merging' of its dual functions. The F/A-352B Longsword's primary role was ground attack missions, acting in support of allied ground units to defeat armoured threats. The Longsword was also tasked with engaging and defeating Covenant single ships such as Seraphs and Banshees, its powerful and variable loadout, coupled with its compromise between speed and armour plating, enabling it to be used against a more diverse group of targets. As a result of this, it could also directly attack enemy warships and aerial targets with reasonable success, with a variable weapons loadout being deployed against Covenant naval ships using high yield conventional or nuclear munitions. This was particularly useful in downing a hostile vessel's shields, ahead of follow-up attacks by more capable UNSC forces. The Longsword was also regularly deployed as protective escort, alongside more dedicated fighter craft, to either warships heading into a battlezone, or smaller craft assaulting a planetary body or hostile capital ship.

When participating in defensive actions around a UNSC planet, the Longsword was launched from both existing ground-based facilities and present UNSC warships. Due to the craft possessing no internal slipspace drive of its own, the Longsword was deployed into offensive action far from UNSC territory solely from UNSC warships, many of which carried large numbers of Longswords in their onboard single ship complements. Due to the Longsword's large size, it could not be deployed from smaller UNSC vessels such as frigates, destroyers and patrol craft. Instead, larger vessels such as cruisers, carriers and larger types had the facilities to hold Longswords, while smaller UNSC ships instead utilised the F-419C Sabre interceptor craft, or the similar F-371 Halberd spatial superiority starfighter.

Layout and Flight

A Longsword performing a high-speed manoeuvre, making use of advanced fly-by-wire and vectored thrust technologies.

The F/A-352B, like its predecessor, featured a highly unconventional airframe dominated by its arrowhead shape. Protruding from its highly backswept leading edge was its cockpit section, where the three crew were positioned, the pilot and weapons systems operator side by side at the front and the combat systems operator (responsible for electronic warfare, sensory equipment and navigation) behind and to the right. From the rear of the craft protruded two oversized engines, on either side of a large tail. With a large surface area, the Longsword featured dozens of control surfaces which, in conjunction with RCS points (reaction control systems) and intuitive fly-by-wire systems, maintained the large craft as an agile one too. While the exterior of the Longsword was virtually identical to the F/A-352A, its interior was entirely different. The 120mm ventral cannons and their ammunition stores were completely removed, and replaced with two internal, retractable hardpoint bays. The formerly expansive interior corridors, cryo tubes and weapons lockers were all removed, the space instead used for improved fusion reactors, internal shield generator, Theran-derived inertial compensators and additional space consumed by the internal weapons bays.

The Longsword's highly unconventional airframe lent it a 'relaxed stability' in flight, meaning it was less stable than more traditional designs. The Longsword was unstable to a point where computerised 'fly-by-wire' or FBW systems were necessary to keep it in flight. The FBW system artificially created stability in the Longsword's flight using precision adjustments, allowing it to remain stable despite its inherent instability. The advantages of this instability were extreme agility in both high speed (hypersonic) and low subsonic speeds. The FBW system was quadruple-redundant, preventing catastrophic incidents stemming from FBW failure, and was highly intuitive in simultaneously following the pilot's inputs and maintaining a controlled manoeuvre. As a result of this system, the F/A-352B was notably more agile than its Covenant counterparts both in and out of atmosphere. The effectiveness of the craft was markedly increased when an Artificial Intelligence was present, as it functioned as a sort of interface between the pilot and fighter (more efficiently than the FBW interface did).

Shielding

The F/A-352B was designed relatively shortly after the Human-Covenant War, and not long after the Sangheili agreed to share technology with the UNSC. As a result it was one of the first mass-produced Human-designed vessels to feature Covenant technology, featuring protective shielding and inertial compensation systems. Although cost initially prevented the Longsword from receiving shield generators, a later update provided this among other upgrades. The Longsword was equipped with the Mark XVII AURORA Projected Energy Barrier, the first production model of any shield generator produced by the UNSC (previous generators had either been directly taken from Covenant vehicles or were not produced in significant numbers). While not comparable in strength to the shielding employed by larger warships, its strength was on a par with that of the Covenant's Seraph, protecting it from a fair volume of fire before actually exposing the Longsword to harm. The shield envelope conformed tightly to the ship's hull, minimising surface area and therefore maximising strength.

Hull

In terms of armour, the Longsword was comparatively well armed for a starfighter, featuring multiple layers of strong, resistant yet lightweight materials that lent it increased resilience to both directed energy and conventional weapons. This armour made use of ACE technology pioneered by The Royal Allegiance and the Ve'nek Dominion, technology that was later shared with the UNSC. The Longsword's armour, like many of its integral systems, was modular, allowing for damaged armour to be removed and replaced, appliqué armour to be added or base armour removed to reduce weight.

Outer Layer

The outer layers of the Longsword's armour were focused more on withstanding plasma attacks, with lower layers offering anti-plasma and anti-ballistic protection. The outer layer of the armour was an energy-ablative superconductive layer composed of variable property energy-reactive regenerative nanomaterials. This nanomaterial absorbed most of the energy from plasma assaults and used it to increase its own strength, its properties changing according to the amount of energy it received. This technology was an evolved form of the plasma-refractive coating used on MJOLNIR Powered Assault Armour, though benefiting from advanced metameterials to turn incoming energy attacks into a defensive ability. As a result the Longsword was able to survive a direct hits from comparatively heavy plasma weapons and remain operational.

Modular Armour

A flight of three Longswords returning from combat against Covenant forces.

Underneath this somewhat unconventional armour was more traditional alloy/composite armour, which provided excellent protection against ballistic and plasma weaponry. This protection used both modular and fixed armour to provide light weight of transport, while still offering full protection from battlefield threats. Though designed as primarily to counter kinetic energy threats, it had excellent chemical energy protection qualities that were further augmented by the implementation of fifth generation captive ERA. It was also considerably more resistant to plasma attacks than previous composite armours.

The outer layer of the composite modular armour assisted in holding the outer armour together, and allowed some slight flexibility yet superior density to engage various threats. Resin impregnated Aramid fabric was wrapped around the composite armour to allow the best protection and structural strength. Below the outer layer was the primary KE and plasma defence, a single piece poured Ceramic DCP plate.

The Ceramic Plate was sandwiched between two plates of CVT (Chromium Vanadium Tungsten) and Austenic Steel alloy. The whole assembly then underwent a hybrid DCP/Triaxial-prestressing method in which the preformed, porous ceramic material was soaked in a bath of molten metal, resulting in super-dense material. As the metal cooled the composite of three plates (one of ceramic, and two of alloy) compressed, increasesing both the density and compressibility of the composite dramatically. This process worked at relatively low temperatures and therefore was more economical than previous production methods. The resulting compound could be molded into complex shapes and offered improved protection at significantly lower weight. This by itself was rather effective but was supplemented by several other materials.

Below the outer plate were several overlapping ceramic 'chevrons'. These chevrons forced any round that was able to penetrate the outer plate to then penetrate the chevrons at a much higher oblique angle than the outer plate. This increased the armour's effectiveness not only by changing the penetrator's vector, but by increasing the thickness plasma had to penetrate. These chevrons were suspended in an plasma-resistant elasticised rubber-like polymer that reduced the shock to the overall plate and transferred much of the impact energy outwards, reducing the stresses on the impact plates. it was also capable of reflecting or absorbing much of the damage caused by directed energy weapons. This material also helped break up penetrating HEAT jets and KE penetrators by causing the chevrons to move around under the force of impact and degrading its overall performance.

Backing the composite matrix was a second composite Alloy/Ceramic plate forcing the plasma or penetrator to again punch its way through at a different vector, forcing the round to fold or break up before it can defeat the final plate. The whole composite was then sealed in a wrap of plasma resistant treated aramid fibres to absorb any remaining spall or plasma splash and attached to the base armour of the Longsword's hull in sections for easy replacement.

Base Armour

The 'Monolithic Armor Plate' (MAP) for the F/A-352B was produced using a process in which sets of inexpensive, thermodynamically compatible ceramic powders (Boron Carbide (B4C) and Titanium-Carbide (TiC)) were blended with thermoplastic polymer binders and then co-extruded to form a fibre. This fibre composite was first braided then woven into the shape of the desired component. The fabricated component was then stacked and pyrolysed to remove the polymer binder and hot-pressed to obtain the base preformed ceramic material for final processing.

The preformed ceramic matrix was still rather porous, and though extremely hard and ductile, was still rather fragile compared to a composite plate. The DCP process avoided extensive shrinkage in the processing of dense ceramic parts, worked at lower temperatures than conventional methods, did not require the use of high pressures and eliminated the need for post-process ceramic machining. The preform was then soaked in a liquid metal alloy bath. The preform absorbed the liquid metal like a sponge; the liquid metal then reacted with the ceramic powder to form a new ceramic compound that filled in pore spaces. The result was a part with a larger internal solid volume, but the exact same external shape and dimensions as the original preform. The DCP method required reaction temperatures of only 1,300C, compared to the 2,000C required for traditional methods, to form very high melting point, covalently-bonded ceramics. Because the final part maintained the shape of the original porous ceramic, post-process reshaping was eliminated. This translated to cost savings for manufacturers, allowing for more armour to be produced.

The finished Composite was extremely dense, lightweight and ductile enough to resist severe impact stress, while providing excellent anti thermal, kinetic and plasma properties and being easy to manufacture and replace when installed in a modular system.

Engines and Powerplant

The main engines of the F/A-352B were two linked Mark XXVIII TEMPEST Fusion Reactors. Here, atomic nuclei fused to form a denser nucleus, accompanied by a net gain of energy. These reactors jointly provided energy for the ship's systems; additionally the fueled the engines by expelling confined plasma at super-high velocities, producing thrust. These engines had exceptional thrust and acceleration, though the craft's top speed of 318,960 kph (Mach 267) was rarely reached in combat. Its speed and agility, though more the former, were substantially affected in atmosphere, although it still maintained its effectiveness. The engines were capable of vectored thrust through numerous control surfaces manipulating the exhaust flow, making up an aspect of the craft's FBW systems and contributing to its agility at both low and ultrahigh speeds.

The Longsword made use of dozens of control surfaces on its exterior to manoeuvre in atmosphere, though they were useless in spatial environments. These, coupled with dozens of RCS points that made the F/A-352B capable of both taxing manoeuvres and microajustments, helped the Longsword maintain staggering maneuverability for a craft of its size.

The F/A-352B also operated Theran-derived inertial compensators, which negated the effects of extreme g-force on crew and enabled them to perform acceleration and manoeuvres previously unheard of. It also effectively reduced the craft's weight somewhat, improving acceleration and other performance characteristics.

Sensors and Electronics

Stealth and Countermeasures

Although not specifically a stealth fighter, the Longsword did make use of several advanced detection reduction methods that rendered it almost invisible on even the Covenant's sophisticated RADAR-based sensors. The hull's outer coat was a matte rubberised polymer spray coating to decrease its UV reflections and to distort LADAR and laser rangefinders. This radar absorbent material (RAM) both heavily reduced its RADAR cross-section, preventing it from being detected, and affecting the enemy's accuracy if it was discovered. It also was shown to decrease the power of direct laser sources for the purposes of target illumination, increasing the craft's survivability. Variable thermostatic circuits maintained the vessel's exterior temperature in accordance with that of its surroundings, rendering it undetectable on thermal imaging. In addition, systems such as the Longsword's covered air intake and engine exhausts were heavily shrouded from detection through use of extensive ablative baffles, which meant that the Longsword was invisible to sensors if its engines ran at 60% or less. The Longsword's hull was also extensively angular, with many flat surfaces and sharp edges, reducing the likelihood of radar bounce-back towards the emitter and heavily reducing its RADAR cross-section (RCS). The F/A-352B made extensive use of heat sinks, exhaust baffles and other passive stealth measures to further reduce its detectability. The result was a craft that, when was indistinguishable from its surroundings on Covenant sensors, and when mobile could be mistaken for a spatial anomaly or sensor malfunction. Combined, these stealth measures served to give the Longsword operating at peak stealth efficiency a RADAR cross-section of under a metre squared, an impressive feat for a craft with a wingspan of over seventy metres. The Longsword's communications, electronics and sensor systems were all optimised for low probability of intercept (LPI) meaning the chance of its detection through these methods was minimal.